Hello, Modus is a brand name of progesterone group of drug medroxyprogesterone. It is not recommended for use during pregnancy as it might rarely cause adverse effects on developing fetus. Some studies have shown that there may be a link between certain birth defects in mothers who are exposed to progesterone. However in clinical practice these problems is not seen in individuals taking modus accidentally in pregnancy. Hope I have answered your query. Let me know if I can assist you further. Regards, Dr. Shinas Hussain, General & Family Physician